The following description of the background of the invention is provided simply as an aid in understanding the invention and is not admitted to describe or constitute prior art to the invention.
Congenital Adrenal Hyperplasia (CAH) is a family of inherited disorders affecting the adrenal glands. The most common form is 21-hydroxylase deficiency (21-OHD), which is inherited in severe or mild forms. The severe form, called Classical CAH, is usually detected in the newborn period or in early childhood. The milder form, called Non-classical CAH (NCAH), may cause symptoms at anytime from infancy through adulthood. NCAH is a much more common disorder than Classical CAH. Fortunately, CAH can be managed with medication and, with adequate care, affected individuals go on to live normal lives.
Cortisol is a steroid produced by the adrenal glands. Cortisol is used in the body to respond to physical and emotional stress, and maintain adequate energy supply and blood sugar levels.
The adrenal glands are controlled by the pituitary gland, a small pea-sized gland at the base of the brain. In health individuals, the pituitary gland releases adrenocorticotropic hormone (ACTH) when there is insufficient cortisol present in the bloodstream. ACTH stimulates the adrenals to produce more cortisol. However, those with CAH have insufficient amounts of the enzyme 21-hydroxylase, which is needed to convert the precursor 17-hydroxyprogesterone (17-OHP) into cortisol. As a result, the pituitary gland continues to sense the need for cortisol and pumps out more ACTH. This leads to an overabundance of 17-OHP, which is then converted in the adrenals into excess androgens (masculinizing steroid hormones).
As such, an individual may be diagnosed with CAH by determining the circulating levels of the affected steroid hormones. Additionally, an individual with CAH may be monitored by tracking circulating levels of these hormones.
Detection of various affected hormones, either alone (see, e.g., U.S. Pat. Nos. 7,348,137 (Caulfield, et al.), and 6,977,143 (Caulfield, et al.) describing detection of testosterone by mass spectrometric techniques; and U.S. patent application Ser. No. 12/207,482 (Ghoshal, et al.) describing detection of dehydroepiandrosterone (DHEA) by mass spectrometric techniques), or as part of a multi-analyte panel, have been disclosed in the art. For example, Carvalho, V., et al., Chromatogr A 2008, 872:154-61, reported a hormone panel which includes cortisol, 17-OH-progesterone, deoxycorticosterone, and 11-deoxycortisol by tandem mass spectrometry in serum; Guo, T., et al., Clinica Chimica Acta 2006, 372:76-82 reported a panel which includes cortisol, 11-deoxycortisol, androstenedione, testosterone, 17-OH-progesterone, DHEA, and progesterone in serum by HPLC-tandem mass spectrometry. Rauh, M., et al., Steroids 2006, 71:450-8, reported a panel which includes 17-OH progesterone, androstenedione, and testosterone by LC-tandem mass spectrometry for the diagnosis and monitoring of hyperandrogenic disorders. Janzen, M., et al., J. Clin Endocrinol Metab 2007, 92:2581-9, reported detection of a panel which included androstenedione, cortisol, 11-deoxycortisol, and 17-OH progesterone by tandem mass spectrometric techniques. Kushnir, M., et al., Clinical Chemistry 2006, 52:1559-67, reported detection of a panel which included derivatized forms of 11-deoxycortisol, 17-OH progesterone, 17-OH pregnenolone, and pregnenolone in blood by LC-tandem mass spectrometric techniques. Lacey, et al., Clinical Chemistry 2004, 50:621-5, and Minutti, C., J. Clin Endocrinol Metab 2004, 89:3687-93, both reported detection of panels which included 17-OH progesterone, androstenedione, and cortisol by tandem mass spectrometric techniques. Shindo, N., et al., Biomedical Chromatogr 1990, 4:171-4, reported detection of a panel which included 17-OH progesterone, 11-deoxycortisol, progesterone, cortisol, testosterone, 17-OH pregnenolone and pregnenolone by plasmaspray LC-MS.